What do all of these experiments have in common?
They’re all formed from a supersaturated solution. Supersatured solutions contains more of the dissolved material than could be dissolved by the solvent (water) under normal circumstances (in this case, room temperature). We will supersaturate these solutions by applying heat. This allows the solvent to hold more solute. (Solute is the stuff we put in the water.)
Here are the recipes for the three experiments. We’ve given you borax, skewers, and baking soda (sodium bicarbonate). You’ll need to provide the water, the sugar, and the vinegar.